Answer:
AC = 16 in.
Step-by-step explanation:
AD = CD = 10 in.
BD = 6 in.
AC = 2(AB) = ?
Apply pythagorean theorem to find AB
AB² = AD² - BD²
Substitute
AB² = 10² - 6²
AB² = 64
AB = √64
AB = 8
Therefore:
AC = 2(AB) = 2(8)
AC = 16 in.
Answer:
Step-by-step explanation:
Area of the shaded region = Area of triangle with base 40 km and height 27 km - Area of circle with radius (12/2) 6 km.

Before we do any solving, we need to simplify both sides.
On the left, we can simplify -2x + 3x - 5 to x - 5.
On the right, we can simplify 6 - 21 to -16.
So we have x - 5 = -16.
Solving from here, we add 5 to both sides to get x = -11.